Jan,
You should set initial values for the parameters.
ROOT can compute these initial values only for "gaus","pol" and "expo"
Rene Brun
Jan Malinowski wrote:
>
> Hi Rooters,
> I have problem with fitting my data by power law function at this way:
>
> Elow=15.0;
> Ehigh=500.0;
> f1 = new TF1( "f1", "pow(10,[0]*x+[1])", log10(Elow), log10(Ehigh)
> );
> f1->SetLineColor(4);
> f1->SetLineWidth(1);
> hist->Fit("f1","R");
>
> I have received result like on the figure which I attached to my e-mail.
>
> The histogram 'hist' was rescaled earlier.
> What is wrong in my code?
>
> Best regards,
> Janek.
>
> --------------------------------------------------------------------------------
>
> Name: fit.eps
> fit.eps Type: Postscript Document (application/postscript)
> Encoding: 8bit
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